This is an old question that is no longer in use.
Images may be missing and the information may be dated.
Which option is true?
No motor vehicles with a connected trailer (C6)
”The sign indicates a prohibition against motor vehicles with a connected trailer of a type other than semi-trailer or centre axle trailer. If the prohibition also applies to motor vehicles with a connected semi-trailer or centre axle trailer, this will be indicated on an additional panel. If the prohibition only refers to vehicle combinations with a trailer whose total weight exceeds a certain tonnage, this will be indicated on additional panel T5, total weight.”
Total weight (T5)
”The panel indicates that the directions of the sign apply to vehicles with a total weight exceeding that stated on the panel.”
No vehicles carrying dangerous goods (C9)
”The sign indicates a prohibition against traffic with vehicles carrying loads that are subject to the labelling requirement of an orange sign according to provisions stipulated pursuant to Act on the Transport of Dangerous Goods (2006:263).”
Parts of both the wrong answers are correct, but the whole answer has to be right and not just part of it.
There is also a driving licence book online (2023).
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